1 /* 2 * Copyright (c) 1997 - 2000 Kungliga Tekniska H�gskolan 3 * (Royal Institute of Technology, Stockholm, Sweden). 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * 3. Neither the name of the Institute nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #include "krb5_locl.h" 35 36 RCSID("$Id: store_mem.c,v 1.10 2000/05/19 14:39:02 assar Exp $"); 37 38 typedef struct mem_storage{ 39 unsigned char *base; 40 size_t size; 41 unsigned char *ptr; 42 }mem_storage; 43 44 static ssize_t 45 mem_fetch(krb5_storage *sp, void *data, size_t size) 46 { 47 mem_storage *s = (mem_storage*)sp->data; 48 if(size > s->base + s->size - s->ptr) 49 size = s->base + s->size - s->ptr; 50 memmove(data, s->ptr, size); 51 sp->seek(sp, size, SEEK_CUR); 52 return size; 53 } 54 55 static ssize_t 56 mem_store(krb5_storage *sp, const void *data, size_t size) 57 { 58 mem_storage *s = (mem_storage*)sp->data; 59 if(size > s->base + s->size - s->ptr) 60 size = s->base + s->size - s->ptr; 61 memmove(s->ptr, data, size); 62 sp->seek(sp, size, SEEK_CUR); 63 return size; 64 } 65 66 static off_t 67 mem_seek(krb5_storage *sp, off_t offset, int whence) 68 { 69 mem_storage *s = (mem_storage*)sp->data; 70 switch(whence){ 71 case SEEK_SET: 72 if(offset > s->size) 73 offset = s->size; 74 if(offset < 0) 75 offset = 0; 76 s->ptr = s->base + offset; 77 break; 78 case SEEK_CUR: 79 return sp->seek(sp, s->ptr - s->base + offset, SEEK_SET); 80 case SEEK_END: 81 return sp->seek(sp, s->size + offset, SEEK_SET); 82 default: 83 errno = EINVAL; 84 return -1; 85 } 86 return s->ptr - s->base; 87 } 88 89 krb5_storage * 90 krb5_storage_from_mem(void *buf, size_t len) 91 { 92 krb5_storage *sp = malloc(sizeof(krb5_storage)); 93 mem_storage *s; 94 if(sp == NULL) 95 return NULL; 96 s = malloc(sizeof(*s)); 97 if(s == NULL) { 98 free(sp); 99 return NULL; 100 } 101 sp->data = s; 102 sp->flags = 0; 103 s->base = buf; 104 s->size = len; 105 s->ptr = buf; 106 sp->fetch = mem_fetch; 107 sp->store = mem_store; 108 sp->seek = mem_seek; 109 sp->free = NULL; 110 return sp; 111 } 112 113 krb5_storage * 114 krb5_storage_from_data(krb5_data *data) 115 { 116 return krb5_storage_from_mem(data->data, data->length); 117 } 118